Vulnerability Database

352,262

Total vulnerabilities in the database

CVE-2026-33318 — @actual-app / sync-server

Improper Access Control

Actual is a local-first personal finance tool. Prior to version 26.4.0, any authenticated user (including BASIC role) can escalate to ADMIN on servers migrated from password authentication to OpenID Connect. Three weaknesses combine: POST /account/change-password has no authorization check, allowing any session to overwrite the password hash; the inactive password auth row is never removed on migration; and the login endpoint accepts a client-supplied loginMethod that bypasses the server's active auth configuration. Together these allow an attacker to set a known password and authenticate as the anonymous admin account created during the multiuser migration. The three weaknesses form a single, sequential exploit chain — none produces privilege escalation on its own. Missing authorization on POST /change-password allows overwriting a password hash, but only matters if there is an orphaned row to target. Orphaned password row persisting after migration provides the target row, but is harmless without the ability to authenticate using it. Client-controlled loginMethod: "password" allows forcing password-based auth, but is useless without a known hash established by step 1. All three must be chained in sequence to achieve the impact. No single weakness independently results in privilege escalation. The single root cause is the missing authorization check on /change-password; the other two are preconditions that make it exploitable. Version 26.4.0 contains a fix.

CVSS v3:

  • Severity: High
  • Score: 8.8
  • AV:N/AC:L/PR:L/UI:N/S:U/C:H/I:H/A:H

Frequently Asked Questions

A security vulnerability is a weakness in software, hardware, or configuration that can be exploited to compromise confidentiality, integrity, or availability. Many vulnerabilities are tracked as CVEs (Common Vulnerabilities and Exposures), which provide a standardized identifier so teams can coordinate patching, mitigation, and risk assessment across tools and vendors.

CVSS (Common Vulnerability Scoring System) estimates technical severity, but it doesn't automatically equal business risk. Prioritize using context like internet exposure, affected asset criticality, known exploitation (proof-of-concept or in-the-wild), and whether compensating controls exist. A "Medium" CVSS on an exposed, production system can be more urgent than a "Critical" on an isolated, non-production host.

A vulnerability is the underlying weakness. An exploit is the method or code used to take advantage of it. A zero-day is a vulnerability that is unknown to the vendor or has no publicly available fix when attackers begin using it. In practice, risk increases sharply when exploitation becomes reliable or widespread.

Recurring findings usually come from incomplete Asset Discovery, inconsistent patch management, inherited images, and configuration drift. In modern environments, you also need to watch the software supply chain: dependencies, containers, build pipelines, and third-party services can reintroduce the same weakness even after you patch a single host. Unknown or unmanaged assets (often called Shadow IT) are a common reason the same issues resurface.

Use a simple, repeatable triage model: focus first on externally exposed assets, high-value systems (identity, VPN, email, production), vulnerabilities with known exploits, and issues that enable remote code execution or privilege escalation. Then enforce patch SLAs and track progress using consistent metrics so remediation is steady, not reactive.

SynScan combines attack surface monitoring and continuous security auditing to keep your inventory current, flag high-impact vulnerabilities early, and help you turn raw findings into a practical remediation plan.